POKEMON FIRE RED AND LEAF GREEN UNKNOWN DUNGEON

Like in Red and Blue, the Unknown Dungeon boasts some high-levelled Pokemon, as well as the unique Mewtwo. You can only get into the Unknown Dungeon once you have fixed the Network Machine on One Island. Refer to the LGFR Walkthrough for more information. To get to Mewtwo, follow this sequence of ladders: E, F, G.